Debt Securities (Tables)

3 Months Ended

Oct. 31, 2022

Debt Securities, Trading and Available-for-Sale [Abstract]

Schedule of Available-for-sale Securities

The following is a summary of available-for-sale debt securities:

	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
	(in thousands)
October 31, 2022:
Certificates of deposit*	$	2,000	$	—	$	(3	)	$	1,997
U.S. Treasury bills and notes		13,894		—		(114	)		13,780
Corporate bonds		3,954		—		(650	)		3,304
Municipal bonds		731		—		(1	)		730
Total	$	20,579	$	—	$	(768	)	$	19,811
July 31, 2022:
Certificates of deposit*	$	2,000	$	—	$	(14	)	$	1,986
U.S. Treasury bills and notes		13,848		—		(114	)		13,734
Corporate bonds		3,966		1		(416	)		3,551
Municipal bonds		3,035		—		(3	)		3,032
Total	$	22,849	$	1	$	(547	)	$	22,303

* Each of the Company’s certificates of deposit has a CUSIP, was purchased in the secondary market through a broker and may be sold in the secondary market.

Schedule of Contractual Maturities of Available-for-sale Debt Securities

The contractual maturities of the Company’s available-for-sale debt securities at October 31, 2022 were as follows:

	Fair Value
		(in thousands)
Within one year	$	15,160
After one year through five years		2,840
After five years through ten years		1,568
After ten years		243
Total	$	19,811

Schedule of Available-for-sale Securities, Unrealized Loss Position

The following available-for-sale debt securities were in an unrealized loss position for which other-than-temporary impairments were not recognized:

	Unrealized Losses		Fair Value
	(in thousands)
October 31, 2022:
Certificates of deposit	$	3	$	1,997
U.S. Treasury bills and notes		114		13,780
Corporate bonds		650		3,304
Municipal bonds		1		250
Total	$	768	$	19,331
July 31, 2022:
Certificates of deposit	$	14	$	1,986
U.S. Treasury bills and notes		114		13,734
Corporate bonds		416		3,514
Municipal bonds		3		2,412
Total	$	547	$	21,646

Schedule of Continuous Unrealized Loss Position for 12 Months or Longer

The following available-for-sale debt securities included in the tables above were in a continuous unrealized loss position for 12 months or longer:

	Unrealized Losses		Fair Value
	(in thousands)
October 31, 2022:
U.S. Treasury bills and notes	$	106	$	856
Corporate bonds		605		3,018
Total	$	711	$	3,874
July 31, 2022:
U.S. Treasury bills and notes	$	72	$	892
Corporate bonds		234		1,731
Total	$	306	$	2,623